Expanded graphite Borax synergism in the flame-retardant flexible polyurethane foams

The main work of this thesis is to study and discuss flame-retardant properties of the flexible polyurethane foam (FPUF) added with borax, expanded graphite (EG), and EG/Borax as flame retardant, respectively. The thermal behavior of samples has been using thermogravimetry (TG) and differential thermogravimetry in air. The activation energies for different stages of thermal degradation are obtained following the equation of Kissinger. The flammability parameters, including limiting oxygen index, rate of heat release, total heat release, yield of CO, yield of CO2, and smoke production rate, were recorded simultaneously. The char structure was studied by SEM, and their thermal stability and evolved gaseous products were examined by TG analysis-Fourier transform infrared spectroscopy. By analyzing these data, it was concluded that most combustion parameters of FPUF were decreased by the treatment, especially for EG/Borax treatment, which indicated a synergistic effect of flame retardancy. Meanwhile, the probable flame retardation mechanism was proposed.